Re: [PATCH] regmap: maple: Don't sync read-only registers

On Tue, Jun 13, 2023 at 09:45:11AM +0200, Takashi Iwai wrote:

regcache_maple_sync() tries to sync all cached values no matter whether it's writable or not. OTOH, regache_sync_val() does care the wrtability and returns -EIO for a read-only register. This results in an error message like: snd_hda_codec_realtek hdaudioC0D0: Unable to sync register 0x2f0009. -5 and the sync loop is aborted incompletely.

This patch adds the writable register check in the loop for addressing the bug.

This should be in _needs_sync().